Yes, the Cod liver oil is extracted from the liver of a cod fish. It is either in liquid or capsule form and is high in omega-3 fatty acids, vitamin A and D. It is known to ease symptoms of arthritis and rickets in children. you can know more about the manufacturing process of Cod liver here, http://www.westonaprice.org/cod-liver-oil/clo-manufacturing
I bet Parrish never ate Parrish's Food. Gentleman's Relish sounds kinky: what do gentlemen do with the anchovy paste? There's a whole world of food name mysteries out there.